Summary: Fixes #18451 I've added another example to NativeAnimationsExample, which makes use of `Animated.substract()`, let me know if the example is not desired / doesn't add much value. Below two GIFs of the new method working on iOS and Android: <img width="320" src="https://user-images.githubusercontent.com/1437605/38154748-165cc5f8-3474-11e8-8b31-504444271896.gif" /> <img width="320" src="https://user-images.githubusercontent.com/1437605/38154749-1679bff0-3474-11e8-80b1-b558d44e0494.gif" /> <!-- Required: Write your test plan here. If you changed any code, please provide us with clear instructions on how you verified your changes work. Bonus points for screenshots and videos! --> https://github.com/facebook/react-native-website/pull/276 [GENERAL] [ENHANCEMENT] [Animated] - Implemented Animated.subtract Closes https://github.com/facebook/react-native/pull/18630 Differential Revision: D7462867 Pulled By: hramos fbshipit-source-id: 4cb0b8af08bb0c841e44ea2099889b8c02a22a4a
